The field of invention is mounting transcutaneous sensors to a subject, and more specifically a skin protection mount for attachment to a subject between the subject's skin and a transcutaneous sensor.
Transcutaneous sensors are well-known noninvasive devices for measuring certain processes and properties of a subject. For example, a transcutaneous blood gas sensor allows for noninvasive measurement of the partial pressure of oxygen and carbon dioxide in the bloodstream by measuring the oxygen and carbon dioxide that permeate through the skin and into the sensor. A typical transcutaneous sensor has an electrode substantially resting against the skin that takes part in detecting the matters of interest. Generally, a layer of gel or solution is placed on the skin so that contact between the skin and the electrode takes places via that gel or solution. Transcutaneous sensors are usually attached to the skin with an adhesive ring having a sticky coating on both sides. One side of the adhesive ring is attached to the sensor, and the other half is attached to the skin. A hole in the center of the adhesive ring allows the electrode in the transcutaneous sensor to substantially touch the skin of the subject.
Commonly, the adhesive ring is attached to the sensor, and is removed from the skin with the sensor. Removal of the sensor occurs on a frequent basis. Transcutaneous blood gas sensors use a heated electrode, which can only be used in one place for a limited time before patient discomfort or an actual bum occurs; premature babies are particularly susceptible to such problems. Typically, such sensors must be removed from a given location on the subject after 2 hours of use in order to prevent discomfort or burns. A transcutaneous sensor may also be removed for placement on a different area of the patient, for replacement, or to allow patient movement without restriction by the sensor. As will be familiar to anyone who has removed an adhesive bandage, removing an adhesive item from the skin can be very irritating to quite painful, and can arouse significant apprehension, particularly in children. More importantly, when the adhesive ring is removed, it can pull up some of the skin layer with it. This can cause a problem with subjects having immature skin or skin disorders. For example, premature infants do not generally have a fully mature cutaneous layer. Yet, transcutaneous sensors must often be placed on premature infants to monitor and ensure their health. Thus, removal of those sensors can cause both pain and skin damage to premature infants.
To reduce skin damage, it is known to place plastic mounting rings on the subject's body at locations where transcutaneous sensing is desired. These plastic mounting rings are made of hard plastic and are thick enough, typically at least a millimeter, to be rigid. Such plastic mounting rings are placed on the subject once, and remain on the subject even when there is no sensor attached to them. A sensor can thus be attached to a plastic mounting ring, then detached from that plastic mounting ring and moved to a different plastic mounting ring, without the detaching process causing pain or skin damage. However, the plastic mounting rings are rigid, and can thus cause discomfort to the subject as he or she moves. They may be particularly uncomfortable for premature infants, for whom the plastic mounting rings are very large--typically about 0.75 inches in diameter--in comparison to their body size.